Process for producing cross-linked polymer containing carboxyl group
AssigneeSumitomo Seika Chemicals Co., Ltd.
InventorsMasato Fujikake, Shinji Kobayashi, Shigeki Hamamoto, Mitsutaka Tabata, Morio Nakamura
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Abstract
There is provided an industrially advantageous process for producing a crosslinked polymer containing carboxyl groups which comprises (a) polymerizing an .alpha.,.beta.-unsaturated carboxylic acid and a crosslinking agent copolymerizable with it in the presence of a radical polymerization catalyst in an inert solvent, (b) heating the polymerized product in the presence of a radical scavenger and (c) removing the solvent. The polymer dissolved in water has high viscosity and excellent flowing properties.
Claims5
A process for producing a water-soluble crosslinked polymer containing carboxyl groups which comprises (a) polymerizing an .alpha.,.beta.-unsaturated carboxylic acid and a crosslinking agent copolymerizable with it in the presence of a radical polymerization catalyst in an aliphatic hydrocarbon solvent to form a slurry, and (b) removing aliphatic hydrocarbon solvent by drying under heating at 50.degree. C. to 160.degree. C. while bubbling oxygen gas diluted with nitrogen gas as a radical scavenger into the resulting slurry.
Dependencies are inferred from the claim text.